RCP<const Number> bernoulli(unsigned long n)
{
#ifdef HAVE_SYMENGINE_ARB
fmpq_t res;
fmpq_init(res);
bernoulli_fmpq_ui(res, n);
mpq_t a;
mpq_init(a);
fmpq_get_mpq(a, res);
rational_class b(a);
fmpq_clear(res);
mpq_clear(a);
return Rational::from_mpq(std::move(b));
#else
// TODO: implement a faster algorithm
std::vector<rational_class> v(n + 1);
for (unsigned m = 0; m <= n; ++m) {
v[m] = rational_class(1, m + 1);
for (unsigned j = m; j >= 1; --j) {
v[j - 1] = j * (v[j - 1] - v[j]);
}
}
return Rational::from_mpq(v[0]);
#endif
}
RCP<const Number> bernoulli(ulong n)
{
#ifdef HAVE_CSYMPY_ARB
fmpq_t res;
fmpq_init(res);
bernoulli_fmpq_ui(res, n);
mpq_t a;
mpq_init(a);
fmpq_get_mpq(a, res);
mpq_class b (a);
fmpq_clear(res);
mpq_clear(a);
return Rational::from_mpq(b);
#else
throw std::runtime_error("Currently supported only if ARB is installed");
#endif
}